The present invention relates to a chain saw, and in particular, to a chain saw capable of being suspended by a rope or the like.
There has been known a chain saw which is driven by an air cooled two-stroke cycle internal combustion engine to cut trunks and/or branches of trees. One among those chain saws of the above-described type which is called a top-mount handle saw is generally used to trim the branches located overhead and is made light and compact so as to facilitate to lift it up even by one hand.
An operator sometimes climbs up a tree and prunes off branches by the top-mount handle saw at high locations in the tree. In that case, in order to ensure his safety, the operator needs firstly to pull a recoil starter to actuate the air cooled two-stroke cycle internal combustion engine on the ground, secondly to climb up the tree while the top-mount handle saw is left on the ground, and finally to lift up the top-mount handle saw from above in the tree by a suspension member such as a rope or the like attached thereto. Upon pulling-up the top-mount handle saw, a projected profile thereof in a pulling-up direction needs to be as small as possible in order to prevent a rotationally driven portion thereof from touching with branches and/or leaves of trees to cause it to rebound therefrom, swing like a pendulum and be unstable.
Accordingly, a first object of the present invention is to provide a chain saw which allows an operator to lift it up from above in the tree without touching with branches and leaves of trees as much as possible.
Further, a second object of the present invention is to provide a chain saw which is light in weight and compact in size.
The first object of the present invention can be achieved by a chain saw having a chain bar portion extending forwardly from a main body, comprising: an attaching portion to which a suspension member is to be attached, the attaching portion being located in the vicinity of a corner portion where a back surface and a bottom surface of the main body meet with each other so that a longitudinal center axis of the chain bar portion forms an angle of not greater than 20 degrees with respect to a vertical line when the chain saw is suspended by the suspension member.
In the present invention, the attaching portion is disposed in the vicinity of the corner portion where the back surface and the bottom surface of the main body meet with each other, so that the longitudinal center axis may be at the angle of not greater than 20 degrees from the vertical line or an elongated axis of the suspension member when the chain saw is suspended by the suspension member. Therefore, when an operator attempts to lift up the chain saw through a gap between branches and/or leaves by pulling the suspension member from above in the tree, the chain saw can be lifted up more easily and safely without the chain bar portion largely protruding out of a projected profile of the chain saw in the pulling-up direction, which otherwise would result in contact with or catch on the branches and/or leaves.
Further, the second object of the present invention can be achieved by an chain saw having an ignition plug arranged in the vicinity of the corner portion and a cover plate portion extending from the vicinity of the corner portion so as to cover the ignition plug, and the attaching portion is formed in the cover plate portion at a location offset from the ignition plug. According to the present invention, since a free space in the plate portion deviated from the ignition plug can be used to form the attaching portion, therefore the device can be made much lighter and more compact.